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<table width="100%" summary="page for Bosco"><tr><td>Bosco</td><td align="right">R Documentation</td></tr></table>

<h2>Boscovich Data</h2>

<h3>Description</h3>


<p>Boscovich data used to estimate the ellipticity of the earth.
There are five measurements of the arc length of one degree of 
latitude taken at 5 different latitudes.  See Koenker (2005) for
further details and references.
</p>


<h3>Usage</h3>

<pre>data(Bosco)</pre>


<h3>Format</h3>

<p>A data frame containing 5 observations on 2 variables
</p>

<dl>
<dt>x</dt><dd><p>sine squared of latitude measured in degrees</p>
</dd>
<dt>y</dt><dd><p>arc length of one degree of latitude measured in toise - 56,700,
one toise approximately equals 1.95 meters. </p>
</dd>
</dl>



<h3>References</h3>


<p>Koenker, R. (2005), &quot;Quantile Regression&quot;, Cambridge.
</p>


<h3>Examples</h3>

<pre>
data(Bosco)
plot(0:10/10,0:10*100,xlab="sin^2(latitude)",
        ylab="arc-length of 1 degree of latitude",type="n")
points(Bosco)
text(Bosco, pos = 3, rownames(Bosco))
z &lt;- rq(y ~ x, tau = -1, data = Bosco)
title("Boscovitch Ellipticity of the Earth Example")
xb &lt;- c(.85,.9,.6,.6)
yb &lt;- c(400,600,450,600)
for(i in 1:4){
        abline(c(z$sol[4:5,i]))
        interval &lt;- paste("t=(",format(round(z$sol[1,i],2)),",",
                format(round(z$sol[1,i+1],2)),")",delim="")
        text(xb[i],yb[i],interval)
        }
</pre>


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